Impact of Left Atrial Volume Index on Discrepancy in Mitral Valve Area Assessed by Two-Dimensional Planimetry and Three-Dimensional Multi-Planar Reconstruction Technique

Background: Mitral valve area (MVA) is technically measured using both two-dimensional (2D) planimetry and three-dimensional multiplanar reconstruction (3D-MPR) techniques; however, studies have always overestimated MVA using the former method. Objectives: This study aimed to assess the correlation between MVA assessed by 2D and 3D techniques and the impact of left atrial volume index (LAVI) on the discrepancy between MVA assessed by two echocardiography techniques. Methods: The data of 75 patients with moderate to severe mitral stenosis assessed by both 2D planimetry and 3D-MPR techniques were retrospectively reviewed. Clinical and echocardiographic variables were evaluated. Left atrial (LA) volume was determined using the biplane area-length method. Results: The mean±SD MVA assessed by the 2D and 3D techniques was 1.03±0.24 cm2 and 0.99±0.25 cm2 with a mean discrepancy of 0.04±0.15 cm2, respectively. A strong association was observed between the MVA values assessed by 2D planimetry and 3D-MPR methods (r coefficient =0.817, P<0.001) indicating a slight discrepancy between the two techniques in assessing MVA. The pointed discrepancy was affected by none of the baseline characteristics and LAVI value. There was an adverse association between LAVI value and MVA measured by both 2D planimetry (r coefficient=-0.291, P=0.011) and 3D-MPR (r coefficient=-0.260, P=0.024) techniques. Conclusion: In contrast to the left atrial dimension, the discrepancy in MVA values assessed by 2D planimetry and 3D-MPR techniques is not influenced by LAVI adjusted for baseline parameters.